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Sea surface temperature (SST) is one of the main factors for drought forecasting. Conventional forecasting models mainly use SST from fixed sea areas (e.g., ENSO), without searching for available SST signals from a global large-scale perspective. Combining with the random forest algorithm, this paper constructs a new meteorological drought forecasting model through regression analysis to screen global SST areas of forecasting significance and takes the Pearl River Basin as an example for application tests. The results are as follows. ① The model can effectively forecast the temporal and spatial evolution of drought, and as the forecast period becomes longer, the forecast accuracy decreases accordingly. ② The accuracy of drought forecast is higher in non-flood season than in flood season, and the coastal area has a better forecast effect than the inland area. ③ The occurrence of droughts in the Pearl River Basin may be related to typical climate fluctuations, such as the El Niño Southern Oscillation and the North Atlantic Oscillation.

Multi-modal sentiment analysis aims to recognize the sentiment expressed by the studied subjects utilizing textual, visual, and acoustic cues. Given the vast application prospects of multi-modal sentiment analysis in domains such as human-computer interaction and intelligent customer service systems, it has gained widespread attention in recent years. The design of fusion strategy significantly impacts analysis results. Different modalities varied on the extent of contributions to the sentiment analysis process, and the textual modality tends to play a crucial role. However, most existing fusion strategies have ignored the issue of uneven distribution of sentiment information across modalities. Therefore, in this study, we introduce a gated fusion network with progressive modality enhancement. To effectively address the challenge of imbalanced sentiment distribution, we propose a progressive modality enhancement approach that facilitates the interaction of sentiment cues. Furthermore, to overcome the limitations of insufficient inter-modal interactions observed in previous works, we introduce a gated multi-modal information interaction module. This module comprehensively exploits multi-modal data, ensuring that each modality can effectively utilize information from others. Experimental results demonstrate that the proposed method achieves highly competitive performance on the CMU-MOSI, CMU-MOSEI, and CH-SIMS datasets. Furthermore, the ablation experiments confirm the dominant role of the textual modality, while indicating that the visual modality generally performs better than the acoustic modality across our experimental settings.

The working gas type had an important effect on the heat transfer performance of the turbulence device in the heater of Stirling engine, but the related researches were scarce, especially under the oscillatory flow. This work investigated the effects of four working gases (i.e., H2, He, N2, and CO2) on the heat transfer characteristics of a heating tube with spiral insert compared with a smooth tube under oscillating flow for a Stirling engine. The transient physical fields under different phase angles in an oscillatory cycle were analyzed, and the Nusselt (Nu) number, pressure loss and outlet temperature of working gas were studied. The results show that the cycle average Nu number of the enhanced tube with H2, He, N2, and CO2 as working gas increased to 1.67, 1.62, 1.61 and 1.72 times when comparing with those of the smooth tube. The cycle average friction coefficient increased to 1.96, 2.37, 2.36 and 2.62 times, respectively. Moreover, the performance evaluation criterion (PEC) values of the enhanced tube using the four types of working gas were all greater than 1 (1.21∼1.33). This implies that the comprehensive heat transfer performance of the heating tube with spiral insert was all improved with the four types of working gas. Moreover, the heat transfer enhancement effect was best when hydrogen was used. While considering the thermodynamic performance and safety reliability, the helium was more recommended. The findings are beneficial to enhance the operating efficiency of a Stirling engine.

Enhancing the heat transfer performance of heat exchangers is crucial for solving energy shortage and environmental pollution problems. Eccentric structure tube, with the advantages of small volume ratio, large heat transfer area, compact structure, and cleanliness, was used in this work to strengthen the heat transfer performance. A three-dimensional numerical simulation method was used to investigate the flow and heat transfer characteristics of the working medium in an eccentric tube under the laminar flow condition. The results display that the Nusselt (Nu) number, friction factor, and comprehensive performance evaluation coefficient (PEC) of the eccentric tube decreased with the increase of lead (s). With increasing eccentric distance, the Nu number and friction factor increased and the PEC first increased and then slightly decreased. At an s of 50 mm and eccentric distance of 4 mm, the PEC could reach 2.43.

Low-speed high-torque direct drive permanent magnet synchronous motor (LHDD-PMSM) can suffer from a typical magneto-thermal coupling problem during long periods of continuous load operation, resulting in temperature rise and leading to reversible demagnetization of the permanent magnets (PMs), thus affecting the motor’s operational performance. In this paper, we experimentally verify the existence of the magneto-thermal problem and investigate methods to reduce the magneto-thermal coupling problem. The paper first researches the on-line detection method of reversible demagnetization. As reversible demagnetization in motors is difficult to identify, we propose a method by measuring the transient PM back EMF of the motor to detect the magnetic properties of PMs in the field. And furtherly, an on-line tester is developed to detect the reversible demagnetization of the LHDD-PMSM. Secondly, this paper analyses the main sources of PM losses and proposes an electromagnetic optimized model combining mixed structure magnetic slot wedge and rotor magnetic insulation slot, so that the eddy current loss of PMs can be greatly weakened. Finally, a bi-directional coupled magneto-thermal simulation model is established with the comparison to a temperature rise experiments, and the model can be used to illustrate the improvement of the magneto-thermal problem of LHDD-PMSM by the loss reduction method proposed in the paper.

A series of Li+, Na+, or K+, Tm3+, and Yb3+ co-doped Bi2WO6 upconversion phosphors were prepared by a high-temperature solid-phase method at 800°C for 3 h. X-ray diffraction showed that Li+, Na+, K+, Tm3+, and Yb3+ doping did not affect the orthorhombic structure of the Bi2WO6 matrix. Scanning electron microscopy images of the Bi2WO6:1% Tm3+, 6% Yb3+ and 1% Li+, 1% Na+, or 1% K+-doped Bi2WO6:1% Tm3+, 6% Yb3+ samples reveal irregular particles with a 0.5–5 µm particle size range; upon Na+ or K+ doping, the particle size increases and the particle surface becomes smooth. EDS analysis shows that the above ions are well incorporated into the powder particles. At 298 K, the relative temperature sensitivities are 0.00144, 0.0016, 0.0024, and 0.0018 K−1 for the 1% Tm3+, 6% Yb3+:Bi2WO6 samples without alkali metal ions and doped with 1% Li+, 1% Na+, or 1% K+ based on the thermally coupled energy level 3F3/3F2 characterization temperature. However, under the same conditions, when using the nonthermally coupled level 3F3/1G4 characterization temperature, the relative temperature sensitivities of these four samples are 0.0378, 0.0166, 0.046, and 0.0257 K−1, increasing by 26.3, 10.3, 19.1, and 13.9 times, respectively. The relative temperature sensitivities of the 1% Na+, 1% Tm3+, and 6% Yb3+:Bi2WO6 samples are the highest at 298 K.

As the concluding activity of the Spring Festival in Northwest China, Liaogan is a distinctive local folk religious practice. This article, taking Qingyang City, Gansu Province, as a case study, employs anthropological fieldwork methods to present the entire process of the Liaogan ritual, trace its historical development and folk cultural connotations, and analysis the role of Liaogan in shaping social cohesion and the daily lives of Northwest people. The paper posits that Liaogan originates from humanity's shared belief in fire and the god of fire, representing a remnant of primitive religious beliefs. The purpose of Liaogan is to ward off evil, eliminate diseases and disasters, and fulfill people's hopes for a bountiful harvest. In this beautiful prayer process, a daily social function of purifying the soul and maintaining social relationships manifests itself in seemingly unconscious activities and continues to serve a symbolic social function in modern society.

The association between tinnitus and psychological resilience is an underdeveloped area of research. This cross-sectional study investigated such associations and factors potentially affecting resilience in 61 patients. Demographic and psychometric data were collected by questionnaires. The Connor–Davidson Resilience Scale (CD-RISC), Medical Coping Modes Questionnaire (MCMQ), Satisfaction with Life Scale (SWLS), General Self-Efficacy Scale (GSES), Big Five Inventory (BFI) and Perceived Social Support Scale (PSSS) were completed by participants. Data were analyzed using independent t-test and Pearson's correlation analysis and multiple linear regression modeling. The CD-RISC score was relatively low (66.97 ± 15.71), negatively correlated with tinnitus (r = −0.276, p

Sanshools, long-chain polyunsaturated amides in Zanthoxylum bungeanum (prickly ash), have important bioactivity. The objective was to assess inhibitory effects and molecular mechanisms of sanshools isolated from supercritical fluid (SCF) extract on human colon adenocarcinoma cells (HCT-116) cultured in vitro. Cells were exposed to various concentrations (0, 50, 90, or 130 μM) of sanshools for 24 or 48 h, with assessment of apoptosis and cell cycle arrest as well as regulatory gene and protein expression associated with apoptosis and the cell cycle. Sanshools profoundly inhibited growth of HCT-116 cells, with hydroxy-γ-sanshool (HRS) being the optimal active component (IC50 = 88.01 μM) inhibiting cell proliferation and having no cytotoxic effect to normal cells (IC50 = 481.52 μM) by CCK-8 assay. In HCT-116 cells, HRS inhibited cell growth, induced morphological distortion, and arrested the cell cycle at G1 phase (50.31 ± 4.13% vs. 72.16 ± 8.14% in Control and 130 μM HRS, respectively), and also caused programmed cell death in a dose-dependent manner. The percentage of apoptotic cells were remarkably increased after treated with HRS (6.2, 11.9, 19.8, and 30.7% for 0, 50, 90, and 130 μM, respectively). Moreover, in HCT-116 cells, HRS significantly inhibited mRNA and protein levels of Cyclin D1, CDK4, PCNA, and increased mRNA and protein levels of P21, P53, Fas, and Caspase 8. Furthermore, inhibitors of P53 and Caspase 8 proteins significantly mitigated the HRS-induced cell cycle arrest and apoptosis. In conclusion, our study provides evidence that HRS induced human colorectal cancer cell apoptosis by up-regulating P53 and Caspase 8.

In order to avoid the disadvantages of the traditional slip ring, such as easy wear and easy accumulation of static electricity, a novel slip ring design method based on series series parallel (SSP) compensation and variable frequency control is proposed. First, the magnetic circuit of the non-contact slip ring is modeled. The leakage inductance and the magnetizing inductance of the loosely coupled transformer, namely the primary side series compensation and secondary side series parallel compensation, are compensated respectively. Next, due to the influence of temperature and other factors, the sensitivity of some components is analyzed, and the relationship between component parameter variation and resonance frequency variation is obtained. After that, a phase difference detection method based on Hanning window fast Fourier transform is proposed, which can avoid the restriction of hardware performance and improve the anti-interference ability. Finally, according to the calculated phase difference and critical quality factor, a variable frequency control method based on zero phase angle is proposed to help the system work at zero phase angle, thereby reducing the loss of reactive power. The simulation results show that when the component parameters change, the proposed method based on SSP compensation and variable frequency control can quickly help the system work in zero phase angle state, and then improve the efficiency of the system. A prototype is designed to verify the proposed method, and the experimental results are basically consistent with the simulation results. Compared with no compensation method, the efficiency of the proposed method is increased by 5%. The research results show that the method proposed has a high robustness.

The casting simulation software ProCAST was used to achieve the simulation of the filling and solidification process of the high Nb-TiAl alloy impeller investment casting. The influence of the casting and filling process on the filling and solidification characteristics of alloy melt filling, shrinkage cavity and porosity was studied, and the corresponding process was optimized. The casting test and the non-destructive testing analysis of the casting were carried out, and the anatomical analysis of the casting was performed to verify the distribution of the shrinkage cavity and porosity. The mechanical properties of the impeller at room temperature and high temperature were studied using attached test rods. The results show that ProCAST software is more accurate in predicting shrinkage cavity and porosity of the high Nb-TiAl casting, and the process scheme is optimized by simulation and prediction results to avoid the formation of large shrinkage cavity and porosity in casting, only micro shrinkage cavity less than 22 μm is existed in the final casting. All castings are fully filled, with the tensile strength about 580 MPa at room temperature and about 450 MPa at high temperature of 850 ℃.

Objective: To realize the rapid on-line detection of defective rice flour. Methods: Non-contact data acquisition of rice flour blocks through cameras, image upload and processing, obtained the contour perimeter and area, approximate contour perimeter and area, approximate contour points and radius of the contour circle. According to the characteristics of rice flour block sample data, the SVM classification algorithm was used to analyze the sample set composed of multi feature data of rice flour block. Results: Compared with five algorithms, the average accuracy of GBDT classification algorithm was 89% with elapsed time of 1.10 s. The average accuracy of KNN classification algorithm was 88% with elapsed time of 0.23 s. The average accuracy of logistic regression classification algorithm was 88% with elapsed time of 0.68 s. The average accuracy of random forest classifica-tion algorithm was 87% with elapsed time of 0.47 s. The average accuracy of tree classification algorithm was 87% with elapsed time of 0.084 s. SVM classification algorithm had the highest average detection accuracy, up to 95%, and the shortest average elapsed time of 0.000 97 s. Conclusion: SVM classification algorithm has the characteristics of high accuracy and low elapsed time, which adapt the on-line detection of defective rice flour.

Abstract Objective: To detect the potential risk factors associated with early mortality in patients who received extensive surgical management, in the form of total arch replacement plus frozen elephant trunk and arch debranching (hybrid repair technique), for acute type A aortic dissection. Methods: The clinical and surgical data of 452 surgically treated patients with acute type A aortic dissection at our center, between March 2010 and December 2016, have been retrieved. Uni and multivariate logistic regression analyses were carried out to detect the effect of various preoperative demographics and different perioperative variables on early mortality. Results: Overall 30-day mortality occurred in 70 out of 452 patients (15.4%). The principal causes of death were multiple organ failure (n=38), cardiac failure (n=18), and severe pulmonary infection (n=10). Risk factors for early mortality were identified with multivariate analysis. Preoperatively, overweight (P

We report dual optical and acoustic negative refraction based on a defect-free phoxonic crystal within a triangular lattice. The phoxonic negative refraction is achieved based on abnormal dispersion effect, by intentionally creating convex equal-frequency contours for both photonic and phononic modes. As a potential application, negative refraction imaging for both photonic and phononic modes is also achieved. Numerical simulations based on the finite element method demonstrate the coexistence of negative refraction and the resultant imaging for electromagnetic and acoustic waves. Compared with the defect-based bandgap effects that need low fault tolerance, phoxonic negative refraction relying on passbands has considerable advantages in realizing controllable propagation of waves. The new scheme for the simultaneous control of electromagnetic and acoustic waves provides a potential platform for designing novel phoxonic devices.

Microbial oil triacylglycerol (TAG) from the renewable feedstock attract much attention. The oleaginous yeast Yarrowia lipolytica has become the most studied for lipid biosynthesis. Fatty acid desaturases catalyze the introduction of a double bond into fatty-acid hydrocarbon chains to produce unsaturated fatty acids. Desaturases are known to enhance lipid accumulation. In this study, we have achieved a significant increase in lipid production and increase the unsaturated fatty acids content in Y. lipolytica. By comparing the expression of the native genes of △-9 stearoyl-CoA desaturase (SCD) and △12 desaturase (△12D), and an exogenous △15 desaturase (△15D) from flax in the strain with deleted peroxisomal biogenesis factor 10 (PEX10) and overexpressed diacylglyceride acyl-transferase (DGA1), we found that the strain with overexpressed △15 desaturase accumulated 30.7% lipid. Simultaneously, we explored the effect of two copies of desaturase genes (12D-SCD, 15D-SCD, 12D-15D) on lipid production, and found co-expression of △12D and △15D accumulated 42.6% lipid. The lipid content was further increased by 56.3% through the deletion of the multifunctional enzyme (MFE1) and the overexpression of acetyl-CoA carboxylase (ACC1). Finally, the lipid productivity of 50 g/L and maximal lipid content of 77.8% DCW are obtained using a 5-L stirred-tank bioreactor during the stationary phase in the engineered YL-10. Our result demonstrated that the △12 and △15 desaturases play an important role in lipid production in Y. lipolytica and provides an effective strategy for biodiesel development.

Hollow niobium oxide nanospheres were successfully synthesized by using prepared three-dimensional (3D) mesoporous carbon as the hard template. The 3D mesoporous carbon materials were prepared by using histidine as the carbon source and silica microspheres as the hard template. The samples were characterized by XRD, BET, SEM, TEM and other methods. The results show that the prepared niobium oxide nanospheres have a hollow spherical structure with an outer diameter of about 45 nm and possess a high specific surface area of 134.3 m2·g−1. Furthermore, the 3D mesoporous carbon materials have a typical porous structure with a high specific surface area of 893 m2·g−1. The hollow niobium oxide nanospheres exhibit high catalytic activity in oxidative desulfurization. Under optimal reaction conditions, the DBT conversion rate of the simulated oil is as high as 98.5%. Finally, a possible reaction mechanism is proposed.

Novel hexagonal nanoplates (NPLs) comprised of mesoporous carbon containing imbedded magnetic Co nanoparticles (CoAl2O4 phase) are prepared through direct carbonization of polydopamine (PDA)-coated CoAl layered double hydroxide (LDH). A uniform PDA coating initially covers the surface of LDH by dopamine self-polymerization under mild conditions. Well-dispersed Co nanoparticles are formed in the NPLs by the partial reduction of cobalt from Co2+ to Co0 with surface carbon during the heat treatment process. The surface morphology and specific surface area of the as-prepared NPLs can be tailored by adjusting the initial dopamine concentration and carbonization temperature. The mesoporous NPLs exhibit excellent sorption of rhodamine B (RhB) dye and fast magnetic separation in aqueous solution. Over 95% of RhB can be adsorbed within 2 min and the adsorption reaches equilibrium after about 30 min. The maximum adsorption capacity approaches 172.41 mg/g. After regeneration, this adsorbent can be recycled easily by magnetic separation and still possess good adsorption capacity for RhB removal, even after five cycles.

Acrylic acid was grafted onto nylon 66 fabric by the electron beam irradiation method. Effects of different grafting conditions on grafting reaction were investigated. Fourier transform infrared spectroscopy(FTIR), thermo gravimetric analyzer(TGA), scanning electron microscope(SEM) and YG065 type fabric strength tester were used to characterize the chemical structures, thermal properties, surface morphology and mechanical properties of these prepared nylon 66 fabric samples. And the anti-dripping performance was evaluated by the vertical burning. The results show that in FTIR spectrum new absorption peeks at 1720.2 cm-1 and other wave numbers are assigned to the carboxyl groups, which imply that acrylic acid is successfully grafted to the nylon 66 molecular. The anti-dripping performance of nylon 66 fabric is improved significantly after grafting. It can be attributed to the cross-linked char layer which subsequently provides a support for the melting fiber. However, the mechanical properties of grafted samples decrease to some extent. With the increase of grafting ratio, the onset temperatures of grafted samples decrease gradually, while the char-forming performance enhances significantly. Besides, the damage length and droplet velocity of grafted samples become shorter and lower, and the tensile strength at break increases slightly.

The effects of texture and precipitates on the plane anisotropy of Cu-Ni-Si alloy under different solid-solution temperature conditions were investigated by X-ray diffraction, electron backscattered diffraction, and transmission electron microscopy. The results show that strength and elongation first increase and then decrease with increasing solid-solution temperature, exhibiting apparently anisotropy. After 800℃ solid solution, the Cu' and S' are mainly texture and the alloy has weak anisotropic properties, which correlates with the coexistence of Brass, Goss, and {011}〈511〉orientation owing to deformed grains. Complete recrystallization can be obtained at high temperature solution (≥ 850℃), the Cu' and S' texture intensity increases, whereas the Brass texture weakens and disappears and the anisotropy increases. δ-Ni2Si precipitation is observed after 850℃ solution and subsequent aging, and the crystal orientation between the matrix and precipitates is [001]Cu//[110]δ and (010)Cu//(001)δ. The fraction of nanosize precipitates decreases significantly with increasing temperature and this improves the anisotropy.

The reversible bonding of microfluidic chips has been developing rapidly with the requirement of reusable microfluidic devices or the need to obtain the samples inside the chip. Traditional bonding methods for polymer-based microfluidics, e.g., thermal bonding, permanently attach the substrate and cover plate. Sometimes, once the chip flow channel is blocked, it is difficult to clean and affect the reusability of the chip. This study proposes a new reversible bonding method for poly (methyl methacrylate) (PMMA) microfluidic chips with the help of stretch release adhesive strips. The designed microchannels were fabricated on the surface of PMMA plates using C[O.sub.2] laser irradiation. Then, stretch release adhesive strips were used as an intermediate layer between the substrate (with microchannels) and another flat PMMA/PS/PC plate to seal the microchannel. The assembled chip sets were bonded at room temperature with bonding strength comparable with other permanent bonding methods. Experimental results show that simply pulling the adhesive layer by applying a shear force can easily detach the intermediate adhesive layer from both the substrate and cover plate to separate the bonded chipset. The proposed reversible bonding method is simple, rapid and has low residue and high bonding strength. Bacterial culture experiments were also conducted to verity the biocompatibility of the proposed bonding method. The proposed reversible bonding technique can be used for polymer-based microfluidic devices that require sample recovery or chip reuse. Highlights * The stretch release adhesive strip can provide high bond strength. * It allows easy peeling for reversible bonding. * It bonds at room temperature with simple operation. * It has good transparency for easy observation of experiments. * It has good biocompatibility. KEYWORDS microfluidics, reversible bonding, stretch release adhesive strip, 1 | INTRODUCTION Microfluidic technology is a technique that utilizes fluids at the micro- or nanometer scale for precise operations and control, with widespread applications in biology, chemistry, medicine, and [...]

[Purpose/significance] The current environmental challenges have become sensitive social and political issues in China. Sorting out existing environmental regulations have important implications for environmental regulation practices and theoretical development. [Method/process] This paper took 1473 CNKI core journal articles in the field of environmental regulation from January 1, 1998 to July 2, 2019 in China as analysis samples，used Citespace visual analysis method for time slicing，and took the keywords as the core，based on the hotspot cluster analysis，clarified the research evolution of environmental regulation and predicted future development trends to explore future research directions in the field of environmental regulation. [Result/conclusion]The research in the field of environmental regulation relies on the Porter hypothesis, environmental Kuznets curve, evolutionary game and other theoretical foundations, and mainly uses the spatial Dubin model, directional distance function and other research methods to analyze the field of environmental regulation in different periods. At present, research in the field of environmental regulation mostly focuses on the relationship between environmental regulation and technological innovation, economic development, industrial competitiveness, industrial structure, etc., but ignores the optimization of the environmental system, the degree of implementation of the environmental system by enterprises, regional differences in the environment, and the important role of cooperation between private organizations and the government in environmental governance, etc. Therefore, these have also become the development trend in the field of environmental regulation in the future.